Aqueous Seeding in Retinoblastoma: Classification and Clinicopathologic Correlation

Area of Science:

• Ophthalmology
• Oncology
• Pathology

Background:

• Retinoblastoma (RB) is the most common intraocular malignancy in children.
• Aqueous seeds are a known complication of RB, but their histopathologic characteristics are not well-defined.
• Understanding the correlation between clinical and histopathologic features of aqueous seeds is crucial for treatment planning.

Purpose of the Study:

• To correlate the clinical types of aqueous seeds with their histopathologic characteristics in primarily enucleated eyes with retinoblastoma.
• To identify potential prognostic indicators associated with aqueous seeding in RB.

Main Methods:

• Retrospective study of 25 patients with retinoblastoma who underwent primary enucleation.
• Clinicopathologic correlation of aqueous seeds, classifying them into three types based on histopathology.
• Analysis of intraocular tissue infiltration and patient follow-up for metastasis and death.

Main Results:

• All 25 eyes were classified as group E RB.
• Clinically, type 1, 2, and 3 aqueous seeds were observed in 36%, 32%, and 32% of eyes, respectively.
• Type 3 seeds were significantly associated with ciliary body infiltration (88% vs. 41%, P=0.04) and occurred in both anterior and posterior chambers in 100% and 72% of cases, respectively.
• 92% of cases showed significant RB infiltration into intraocular tissues.
• Metastasis and death occurred in 12% of patients over a mean follow-up of 57 months.

Conclusions:

• Aqueous seeds in RB demonstrate three distinct histopathologic types, analogous to vitreous seeds.
• The presence of aqueous seeds, particularly type 3, is associated with high-risk histopathologic features and warrants a cautious approach to conservative management.
• Conservative treatment strategies should consider involvement of both anterior and posterior chambers when aqueous seeding is present.